Harvesters are used in the agricultural industry to harvest a variety of crops. Headers for harvesters generally use belts on rollers to move the harvested crops from lateral areas of the header to a central area for processing. As demand for larger harvesters with increased capacity increases, the harvester must either drive the belts faster or the headers must be wider to accommodate more crop. There are many challenges associated with driving the belt faster, including the increased wear of parts, power costs, and maintenance costs.
In order to make a header wider while still adhering to changes in terrain, the header must be flexible. Generally, such flexibility is accomplished by the use of two or more belt and roller assemblies, and a pivot joint of the draper frame between the two assemblies. The pivot joint is generally positioned between the two belt and roller assemblies, resulting in a gap between the rollers through which crop can be lost during harvesting.
For example, FIG. 1 shows a front view of a traditional harvester 10. The harvester 10 includes a header 12, such as the one described in U.S. Pat. No. 8,087,224 (“the '224 patent”). The header 12 can include a central section 14 with right and left wings 16, 18 capable of pivoting relative to the central section 14 to accommodate uneven terrain while providing the wide header 12 for greater crop capacity. A lateral plane 20 extends through the header 12 and can generally be substantially parallel to the ground 22 during normal use. The header 12 includes a draper belt system 24 disposed in the central section 14 and the right and left wings 16, 18 to assist in guiding crop from the header 12 into a processing system 26 within the harvester 10. The central section 14 and the right and left wings 16, 18 can include reels 28.
FIGS. 2 and 3 show perspective and detailed views of the header 12. Although discussed with respect to the left wing 18, it should be understood that the right wing 16 has a similar structure and function. The header 12 includes a draper belt system 24 for transferring harvested crop from the left wing 18 to the central section 14 such that the central section 14 can introduce the crop into the processing system 26. The draper belt system 24 includes a first draper belt assembly 30 at the left wing 18 and a second draper belt assembly 32 at the central section 14 disposed adjacent to the first draper belt assembly 30.
The first draper belt assembly 30 includes a first roller 34, a second roller 36, and a belt 38 looped around the first and second rollers 34, 36. The second draper belt assembly 32 includes a third roller 40, a fourth roller 42, and a belt 44 looped around the third and fourth rollers 40, 42. As the belt 38 is rotated in a counterclockwise direction, crop collected on the belt 38 is transferred from the left wing 18 to the belt 44 of the central section 14. The header 12 includes a draper frame 46 associated with the left wing 18 and a draper frame 48 associated with the central section 14. The draper frames 46, 48 connect at a pivot joint 50 such that the left wing 18 can rotate relative to the central section 14.
The first roller 34 and the third roller 40 each have their own central longitudinal axis 54, 56 about which the respective first roller 34 and third roller 40 rotate. As shown in the detailed view of FIG. 3, due to the separate belt assemblies 30, 32, the first and third rollers 34, 40 are separated by a gap 58 to allow for rotation of the draper frame 46 relative to the draper frame 48 without interference between the belts 38, 44. The gap 58 results in the axes 54, 56 being separated by a distance 64, which the '224 patent describes is constant. Although not clear or described in the '224 patent, it appears that the distance 64 is kept constant by a frame 35 surrounding the rollers 34, 40, which locks the spacing between the axes 54, 56. Such a frame 35 can be difficult to construct, can require additional maintenance of parts, increases the cost of production, and can increase the time necessary for replacement of parts.
Due to the gap 58 and the separation between the rollers 34, 40, a portion of the harvested crop can be lost during transfer of the drop from the left wing 18 to the central section 14. A similar loss in crop occurs during transfer of the crop from the right wing 16 to the central section 14.